So the DLVJ1 has four serial ports. According to the info at http://www.ibiblio.org/pub/academic/computer-science/history/pdp-11/hardwar… they essentially appear as four separate gizmos, with independant CSRs and vectors. So should I therefore set NKL to 5 (the console plus these four) and then have appropriate entries for devices 1 through 4 in /etc/dtab? Sounds like it. My DHV11 seems to work happily, so I already have rediculously more serial ports than I need. -- David Evans (NeXTMail/MIME OK) dfevans(a)bbcr.uwaterloo.ca Ph.D. Candidate, Computer/Synth Junkie http://bbcr.uwaterloo.ca/~dfevans/ University of Waterloo "Default is the value selected by the composer Ontario, Canada overridden by your command." - Roland TR-707 Manual